<template>
  <div class="test">
   hello
    <div id="app-3">
      <p v-if="seen">现在你看到我了</p>
    </div>
  </div>

</template>

<script>
export default {
  name: 'HelloWorld',
  data () {
    return {
      msg: 'Welcome to Your Vue.js App',
      seen : true
    }
  }
}
</script>

<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
  .test{color:red}
</style>
